Thermal protector and alarm.



No. 812,184. v PATENTED FEB. 13, 1906. F. B. COOK. THBRMALIPRO'IKEGTOB. AND ALARM.

APLIOATION YILED DEO.1 8, 1902 2 SHEETS-SHEET l.

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110.812,104. f f PATENTBD FEB. 1a, 1900.

P. B. 000K.

THERMAL PROTECTOR AND ALARM.

' APPL'IGATION FILED 11110.18. 1902 2 SHEETS-SHEET 2.

LINE SWITCHBOHRD.

i;- 11mm FRANK B. COOK, OF CHICAGO, ILLINOIS.

THERMAL PROTECTOR AND ALARM.

Specification of Letters Patent. Application led December 18, 1902. Serial No. 135.676.

.Patented Feb. 13', 1906.

To all rbh/m t may concern: l

Be it rknown that I, FRANK B. COOK, a citizen of the UnitedStates of America, and a resident of Chicago, `Cook county, Illinois, have invented a certain new and useful Improvement in Thermal Protectors and Alarms, of which the following is a specification. i

My invention relatesto devices for protecting electrical circuits against the encroachment of dangerous or abnormally large currents.

It relates more particularly to a form of protector involving the use of both heatcoils and carbon lightning-arresters. As is well known, the said `heat-coils are adapted to automatically open the circuit upon the encroachment of currents only slightly in eX- cess of normal, sometimes called sneak-l currents. The carbon lightning-arresters, asis also well understood, protect the instruments'in the circuit against lightning discharges and provide a path to ground for a high-potential current.

Generally stated, the object kof lmy invention is to provide an improved construction and arrangement whereby both heat-coils and carbon lightning-arresters may be conveniently and effectively employed in conjupction with each other and organized into a self-contained and improvedy piece of appa- V ratus for protecting electrical clrcuits and instruments against the encroachment of dangerous or abnormally strong currents.

A special object is to provide an improved vconstruction and arrangement whereby a number of heat-coil devices maybe arrangedina couple of parallel rows at each side of a 'grounded plate or support and whereby the carbon lightning-arresters may be vc'onveniently and effectively mounted in a row along the edge of said plate. i

.inotherobfect is to provide an improved, simple, and effective arrangement whereby each heat-coil when operated willy be capable of closing the circuit of a local alarm. It

"is also `an object to provide bertain details and features of improvement tending to increase the general efficiency and serviceability of a combined heat-coil and carbon lightningarrester protector of this particular character.

To the foregoing and other useful ends my invention consists in matters hereinafter set forth and claimed.

The thermal protector herein shown forms 'openings d.

heat-coils and lightning-arresters which arev mountedupon this plate. Fi 2 is an end view of the devices shown in' ig. 1. Fig. 3 is a section on line 3 3 in Fig. 1. Fig. 4 is a diagram of the circuits involved in m irnproved rotector and alarm device. ig. 5 is an enliarged longitudinal section of one of the-heat-coil devices involved in my improved protecting apparatus.A e

Referrin to Figs. k1, 2, and 3, A represents a portion o -a metal strip or iron plate upon which the heat-coils and carbon lightning-arresters are mounted. It will,be readily understood" that this strip orplate can be of any suitable length consistent' with the use and 1 pur oses ofthe device asa whole and accor ing to thevnumber of coils and lightningarreste'rs which it 'may be desired to mount thereon. Near the upper edge of this late va number of separating or spacin ro s or strips of insulation B are inserte through openings a, and farther down on the plate a number of somewhat similar rods or strips of insulation C are inserted `through Th insulating rods or strips B pro'ect at each eiild of the plate and are preferably connected b metal rods t, which latter form part ofthe" alarm-circuit, as will similar hereinafter more fully a pear. The rods of I rubber or other like insu ating material C are each preferably provided with a rod or metal core c, which, as will be observed, projects at each end and which is provided with a numberv of small nuts c. Upon each rod c a number ofk springs D, D', E, E, F, F, G, and G are mounted and distributed, as illustrated in Figs. 2 andf3. The line-terminal e may .be a part of the spring E, while the other lineterminal gis preferably formed of a separate piece and electrically connected by the-metal sleeve g with the springs Gr and G. The switchboard-terminal f can be formed integral with the spring F, while the other switchboard-terminal c2 is preferabl formed of'a separate piece and electrica' ly connected with the, metal rod c. It will also be observed that the springs D and D are electrically connected with the rod c. The

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springs E and E', the springs G and G', and l connected in series.

also the springs F and IF. are preferably insulated from the core or rod c.'

Theupper ends ofthe springs D, E, F, and G are preferably notched and ada ted to receive the groovedheads of the cy indric heat-coil devices H. These heat-coil devices can be of any suitable or approved construction, but are preferably of the character shown in Fig. 5. In this figure it will be seen that the head h is connected with the opposite or similar head h through the medium of the two stem ortions h2 and h3 and the interposed solder 4. A coilo wire h5 is Wrapped around the two stems thus held together by the solder. The stem portion h2- is insulated from the head 7i by a mass of insulation h6. One terminal of the heating-coil h5 is secured-to the head ,if,while the other terminal is secured to the stem h2. With this arrangement it is obvious that the two heads h and h', the hollowr stem h2, and the heating-coil and solder are all It follows, therefore, that the passage of an undue or abnormally strong current through these elements wid cause the heating-coil h5 to develo suflicient heat to melt the solder, thereby a lowing the two heads to be pulled apart b the springs upon which they are supporte and at this juncture it will be understood, of course, that the springs D, E, F, and G are normally under tension when the cylindric heat-coils H -are inserted in place, as shown inthe draw- Thus, as will be seen, the switchboard ings. and line springs, with the cylindric heat-coils mounted upon their ends, are arranged in banks or groups at eachside ofthe ilat metal plate or support A. A'device of this character is capable of use in various connections. For example, it may be installed in a telephone-exchan e, and in such case the line conductors-wid be secured to the line-terminals e and g, while the switchboard-conductors will be united with the terminals f and c2 Thus connected the heating-coil of each Aheat-coil device will constitute part of a line-circuit, and consequently all curv rents traversin this circuit will pass through the springs an 'heat-coils. Now should an unduly strong or abnormally large current show its presence in one of the line circuits tlie heat developed by the heating-coils h5 in this circuit will cause a melting of the solder h4 and a consequent o ening of the circuit, due to the separation ci) the' sectional conductors involved in each heat-coil by the' action of the released springs, and in addition to the opening of. the line-circuit in this manner each line-spring iscapable of establishing a connection to ground through the medium of the contact e2, one of which is mounted on each line-spring and which are ada ted when the line-s rings are released to ma e contact with the rass mounting-strip I, which is secured to the upper edge of the metal strip A, the latter being preferably of cold-drawn steel. Asishown in Fig, 4, this strip or plate A is preferably grounded at X.

v In order to protect the circuits against lightning discharges, a plurality of carbon lightnin -arresters J are mounted in a couple o paral el rows along the brass mountingstrip I. The arrangement is such that a carbon lightning -.arrcster is associated with eachheat-coil device. rester may comprise acouple of carbon b ocks d, with a mica or other like dielectric inter- Eosed between them. At one side these locks are held in place by thel auxiliary line-sprin s E, while at the other side the blocks are eld in place b the auxiliary linesprings G. Thus each ine-terminal e and g is ada ted to connect a line conductor with botli a carbon lightning-arrester and a heat-coil, the latter serving as the medium of connection between the line conductor and the instruments to be protected. With this arrangement all lightning discharges will be conducted from line to round through the medium of the carbon b pcks, the discharge or highotential current arcing across from one car on block to another in'the wellknown manner. l -As a matter of further and special improvement the switchboard-springs D, D', and F are adapted to close the circuit of a local alarm L when either one of the heatcoils is operated or disrupted by the passage of a current above the normal. This is accomplished by connecting the rods b in a normally opened circuit, includin the said alarm and the battery 1. With t 's arrangement the two rods when electrically connected g by the springs F and F, for example, comf plete the circuit and cause the alarm device '.to give a signal. This is clearly shown in i coils operate to normally maintain the sprin s F and F out of contact with the two rods f but when these springs are released by the giving way of the connection in the heat-coil the circuit is closed and the signal o erated. In this way an attendant can rep ace-the burned-cut or operated heat-coil as soon as the alarm is sounded. l Thus it will be seen that I provide a compact and self-contained vpiece of rotective apparatus which `is ada ted for use 1n connection lwith all kinds o electrical apparatus and instruments, but which is more particularly adapted for installation in a telethe switchboard apparatus a ainst the encroachment of either abnorina ly strong currents or currents only slightl in excess of normal. Furthermore, it will be seen' that the construction permits of the ready repair and substitution of all parts and permits the heatcoils' and lightning-ariesters to be conveniently mounted in banks or, roups. Again,

.with the heat-coils andlig tning-arresters Each lightnin -ar- IOC ' Fig. 4, wherein it will be seen that the heat- IIO phone-exchange for the purpose of protecting I of metal, line and switchboard springs mountmounted upon a flat metal plate it is possible to easily install and remove the protective apparatus and to arran e them in a position to be easily and carefully inspected. Other advantages will be obvious to those skilled in the art. y l

The wiring or method of applying connections is obviously facilitated 'and rendered more satisfactory by reason of the line-termiyss nals all being ouped at one side of the support Av and t e switchboardterminals all grouped at'the other side thereof.

W at I claim as my invention is- 1. A protector, comprising a plate of metal, rods inserted transversely through said plate ed upon said rods, the line-springs between the switchboard-springs and plate, heat-coil devices .removably mounted upon the ends of said springs, a brass mounting-strip secured to the edge of said plate, the switchboard-springsnormally ullingu onthe heatcoil devices, and away'v om saidp plate, and a pair of parallel rows of' carbon lightning-arresters mounted upon said brass strip, each carbon li rhtning-arrester being electrically connecte with an adjacent line-spring together .with a normally open alarm-circuit,

each of said outer switchboard-springs being adapted, when released, to constitute part of the alarm-circuit.

2. A protector, comprising a flat plate lof metal, rods of insulation inserted, transversely throughsaid plate, line and switchboard springs mounted on certain of said rods, the other rods of insulation serving to separate the different .pairs of line and switchboard springs, and heat-coildevices mounted upon .said springs, the switchboard-g rings normally ulling u on the heat-coil evices, and awa om sai plate together with a normal y open alarm-circuit, each of said outer switchboard-springs being'adapted, when re-l leased, to constitute part of the valarm-circuit. 3. A protector, comprising a flat plate 'of metal, line and switchboard' springs arranged in airs and mounted in two rows, one at each si e of said plate of metal, said springs all being insulated from said plate `o metal, and heat-coil devices removably mounted upon the ends of saidsprings, .the switchboard-` s rings normally pulling upon the heat-coil evices, and away from saieLplate together with a normally open valarm-circuit, each of said outer switchboard-springs being adapted, when released, to constitute part ofl the alarm-circuit.

4. In a self-contained piece of'protective ate, lineand' switchboard springs mounted in fpairs at one side of said plate, other line an switchboard springs mounted in similar apparatus, 'the combination of a flat metal P Apairs at theother side of said plate, all of said sprin s being insulated from saidlate, heatcoil evices removably mounte upon the ends of said springs, the switchboard-springs.

5. The combination of a llat metal plate, a

row of rods or stri s of insulating :material inserted transversely through the other row. of rods or strips of insu ating material inserted through the plate, each of said last-mentioned rods being provided with a metal core, line-springs mounted on said last-mentioned rods and arranged at each side. of the said late, said line-springs being insulated from t e said metal cores, switchboard-springsalso mounted lupon the said last-mentioned rods, the switchboard-springs at one side of the plate being electrically connected with the cores, the other switchboardsprin s being insulated from the said cores, and eat-coildevices removably mounted upon the ends o said springs, -the Afirst-menlate, anv tioned rods of insulation serving to'maintain the proper distance between the pairs of line and switchboard springs.

piece -of protective apparatus, of a ilat metal plate, rods or strips of insulation inserted IOO through the upper portion of said plate, said l rods being connected at each side by metall rods, switchboard-sprin s suitably mounted and insulated from sai plate, said switch- Vboard-springs being normally out of contact with said metal rods, but ada ted to-make contact with said metal rods, ine-s rings, each line-s -ring being associated wit a'switchboar spring, and heat-coil devices removabl mounted upon said s dy evices,'and away from said plate together with a normally open alarm-circuit, each of said outer switchboard-springs being adapted, when released, to constitute part ofthe alarm-circuit.

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7 The combinationin a protector, of' a y flat metal plate, suitable pieces of insulation inserted transversely through said plate,

alarm-circuit contacts mountedon certain of' said ieces of insulation, line .and` switchboar springs mounted on rthe other pieces of insulation, saidV s witchboardsprings being adapted to engagev the said';c`ontacts,'but` adapted to be normally out of contact lwith the same, suitable heat-coil devices removably 'av plied to the'ends of; said line and switch oard s rings, the switchboard-springs normally pulling upon thelieat-coil devices,

IIO .I'llgS, the switchboar j v s rings normally 'pu ling upon the heat-coil zio paratus, comprising a fiat strip adapted to serve as a mounting or support, line and switchboard springs mounted 1n pairs at each side of said strip, heat-coil devices removably applied to the ends of said springs, the switchboard-springs normally pullinr upon theheat-coil devices, and awayfroiii said plate,-

and carbon lightning-arresters mounted in two parallel rows along the edge of said late, one block of 'each li 2litning arrester eing electrically connecte with an adjacent linespring,.and the other block of each li htningarrester being electrically connecte with a member which is adapted'to be connected to ground together with a normally open alarm-circuit, each of said outer switchboardsprings being adapted, when released, to constitute part of the alarm-circuit.

9. In a device'of thecharacter described, the combination of a suitable support, outer switchboard-springs and inner line-springs suitably mounted at one side of saidsupport, A

heat-coil, devices removably applied to the ends of said springs ,-a normally open roundcircuit including said support, eac linespring when released being adapted to constitute part of said ground-circuit, and a normally open alarm-circuit, each of said outer switchboard-springs being adapted when released to constitute art of said alarmcir cuit, and the line-springs being mounted intermediate of the said support and switchboard-sprin s.

10. In a device of the character described, the combination of a metal sup ort, an inner line-spring and an outer switcliiboard-spring suitably mounted at one side of said support, a heat-coil device removabl applied to the ends of said springs, a norma ly o en groundcircuit including said support an line-spring in series, and an alarm-circuit normally open at two points and including said switchboard-spring, the line-spring being mounted intermediate of the support and switchboard-spring.

11. A thermal protectorand alarm apparatus, comprising ametal' support, a row of heat-coil devices mounted at each side of said sup ort, a normally open ground-circuit inclu ing said support, line-terminals connected with the said heat-coil devices and all mounted at one side of said support, and switchboardterminals also suitabl -connected with said heat-coil devices and a l mounted at the other side of said sup ort, said heat-coil devices having line andJ switchboard sprin s, the line-springs bein mounted interme iate of the support an switchboard-springs, together With a normally open alarm-circuit, each switchboard-spring when released being adapted to constitute part of said alarm-circuit.

12. thermal protector and alarm apparatus, comprising a metal support, line and switchboard springs mounted in pairs at each side of said support, heat-coil devices removably applied to each of said pairs of s rings, line terminals connected with sai linesprings and all mounted at one side ci said support, switchboard-terminals suitably ,con-

nected with said switchboard-springs and all mounted at the other side of said su port, a normally open ground-circuit including said support, each line-spring when released being l adapted to constitute part of said groundcircuit, togetherwith a normally open alarmcircuit, each switchboard s ring When released being adapted to constitute part of the alarm-circuit.

13. In a device of the character described,

the combination of a suitable s up ort, line and switchboard springs mounte on said support, an auxiliary spring between .the said line and switchboard springs, a heat-'coil device applied to the ends of the line and switchboard springs and holding the same normally under tension, a` pair' of. metal rods bot l mounted between the line'and switchboard sprin s, one rod being normall out of contact with t e auxiliary springend` t e other rod being normally out of contact Withthe switchboard-spring, whereby both rods. are engaged by their respective springs when the switchboard-spring is released and moves awa mal o en alarm-circuit including said rods and inc uding also said auxiliary.and switchboard s rings.

14. he improved thermal protector and alarm apparatus comprising a support with a row'oil thermalcut-outs at each side thereof, together with line-terminals and switchboard-terminals, the line-terminals all being arranged at one side of said support, and the switchboard-terminals all at the other side of said support, substantially as shown and described.

Signed by me at Chicago, Cook county, Illinois, this 11th day of December, 1902.

FRANK B. COOK.

from the rods, together with a nori IIO 

